Anomaly: Warzone Earth announced for XBLA

It's the same game that launch on PC earlier this year, padded out with six new Tactical Trials levels not included in the original.

Pegged as the first ever 'tower offence' game, it sees you attempting to liberate various major urban centres occupied by invading alien forces.

The PC release impressed Eurogamer's John Teti back in April.

"Anomaly is a reversal of the standard tower defence format: the evil, faceless aliens place towers along a path, and your troops attempt to survive their gauntlet," read his 8/10 Anomaly: Warzone Earth review.

"The switcheroo could be considered a gimmick if the developers at 11 bit studios weren't so clever about it. They haven't simply swapped roles; they've re-engineered the form."